Skim is a Free macOS PDF Reader and Note-taker for Scientists

Skim is a Free macOS PDF Reader and Note-taker for Scientists
Photo by Milad Fakurian / Unsplash

Skim is a PDF reader and note-taker for OS X. It is designed to help you read and annotate scientific papers in PDF, but is also great for viewing any PDF file. Skim requires OS X 10.10 or higher.


  1. Lightweight app.
  2. View and read small and large PDF files.
  3. Supports multiple languages: English, French, Italian, German, Spanish, and Russian.
  4. Opens multiple document in tabs.
  5. Define your export templates.
  6. Adding and editing notes.
  7. Smart cropping tools.
  8. Advanced printing options with notes.
  9. Highlighting important text, including one-swipe highlight modes
  10. Making "snapshots" for easy reference
  11. Navigation using table of contents or thumbnails, with visual history
  12. View all your notes and highlights
  13. Convenient reading in full screen
  14. Comes with a long list of built-in shortcuts for all the popular functions
  15. Giving powerful presentations, with built-in transitions
  16. Handy preview of internal links
  17. Focus using a reading bar
  18. Filter and search your  notes
  19. Magnification tool
  20. Extensive AppleScript support
  22. Saving passwords in Keychain
  23. Export notes as text
  24. Automatic download of remote PDFs
  25. Support for Apple Remote Control
  26. Interaction with LaTeX, SyncTeX, and PDFSync
  27. Integration with BibDesk and other third party applications
  28. Spotlight support
  29. Highly customizable
  30. Can read text files with the command-line Skim tools.
  31. Join notes easily

Custom page transitions

Skim PDF supports custom page transition, here is a list of animations it support:

  • Hole Transition
  • Radar Transition
  • Blinds Transition
  • Strips Transition
  • Meltdown Transition
  • Acceleration Transition
  • Blur Transition
  • Pinch Transition
  • Box In Transition
  • Box Out Transition
  • Split In Transition
  • Split Out Transition
  • Cover Transition
  • Uncover Transition
  • Sink Transition

Custom Export Template

Skim PDF allows you to export your notes to many formats with support of several built-in custom templates:

  • Text Notes as RTF An RTF template exporting only text for text and anchored notes
  • None-Markup Notes as RTF An RTF template exporting only text, anchored, circle, and box notes
  • Notes as Plist A text template exporting XML conforming to Apple's property list DTD
  • Notes as XML A text template exporting XML with a custom DTD
  • Notes and Pages as RTFD An RTFD template exporting notes and thumbnails of all pages
  • Notes as Markdown A template which exports a Markdown-formatted bulleted list of annotations with the article name as a header on the top of the list.


The Skim PDF viewer is released under the BSD License.


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